GNGTS 2018 - 37° Convegno Nazionale

GNGTS 2018 S essione 1.3 253 As for the H/V ratios, our data are in agreement with the results obtained by Vassallo et al. (2017), mostly for the peak in the range 0.4-0.8 Hz, which can be related to the presence of the laccolith at a depth of about 800-1000 m (Carlino, 2012). References Bettig B., Bard P.Y., Scherbaum F., Riepel F., Cotton F., Cornou C., Hatzfeld D.; 2001: Analysis of dense array noise measurements using the modified spatial auto-correlation method (SPAC): application to the Grenoble area. Boll. Geof. Teor. Applic., 42 , 281-304. Carlino S.; 2012: The process of resurgence for Ischia Island (southern Italy) since 55ka: the laccolith model and implications for eruption forecasting. Bulletin of Volcanology, 74 (5), 947–961. D’Auria L., Giudicepietro F., Tramelli A., Ricciolino P., Lo Bascio D., Orazi M., Martini M., Peluso R., Scarpato G., Esposito A.; 2018: The Seismicity of Ischia Island. Seismological Research Letters, 89 (5): 1750–1760. doi: https://doi.org/10.1785/0220180084 Lacoss R., Kelly J., Toksöz, M.; 1969: Estimation of Seismic Noise Structure using Arrays. Geophysics, 34 . 21-38. 10.1190/1.1439995. Strollo R., Nunziata C., Iannotta A., Iannotta D.; 2015: The uppermost crust structure of Ischia (southern Italy) from ambient noise Rayleigh waves, Journal of Volcanology and Geothermal Research, 297 , 39–51. Vassallo M., Galluzzo D., Sapia V., Nardone L., Pischiutta M., Petrosino S., and the Emersito++ working group; 2017: Site effect studies following the 2017 Mw 3.9 Ischia earthquake: the Emersito++ Task Force activities. Geophysical Research Abstracts, 20 , EGU2018-16452-1 Wathelet M., Jongmans D., Ohrnberger M.; 2004: Surface wave inversion using a direct search algorithm and its application to ambient vibration measurements, Near Surface Geophysics, 2 , 211-221. MT. ETNA 2017: A MULTIDISCIPLINARY INVESTIGATION TO EXPLORE THE RECENT DYNAMICS OF MAGMA ASCENT AND INTERACTION M. Giuffrida 1 , M. Viccaro 1,2 , F. Zuccarello 1 , M. Scandura 1 , M. Palano 2 , S. Gresta 1 1 Università di Catania, Dipartimento di Scienze Biologiche, Geologiche e Ambientali,Catania, Italy 2 Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania - Osservatorio Etneo, Catania, Italy Introduction. In the last few decades, several eruptions have taken place at Mt. Etna in relatively short time span, passing from period of entirely effusive activity to strongly explosive (i.e., violent Strombolian to lava fountains). Since 2011, the eruptive behavior was dominantly explosive with two major cycles of paroxysmal eruptions as those of 2011-2013 at New South East Crater (NSEC) and 2015-2016 at the Voragine Crater (VOR). A new drastic change of the eruptive style was observed during the first months of 2017, when the activity turns again to dominantly effusive, giving rise to a short sequence of weak Strombolian explosions and lava flow emissions between February and April. Understanding and forecast such eruptive phenomena at Mt. Etna are of prominent importance due to the high population density on its slopes. In order to enable a better knowledge of the volcanic phenomena in progress, the observation and monitoring systems have been significantly implemented in recent years, and a higher quantity and quality of instrumental data associated to recent eruptions have been collected (Spampinato et al., 2015; Gambino et al., 2016). In particular, the rapid growth of continuously recording geodetic networks enhanced acquiring extensive datasets that largely improved our current knowledge of the magmatic plumbing system. However, in the case of articulated plumbing systems, geodetic data modeling alone are unable to entirely deconvolve complex evolutionary dynamics of magmas or to comprehensively track the ascent paths of magmas and potentially resolve their temporal relationships without relying on compositional information preserved in volcanic minerals and rocks. In this study, we show that geochemistry and diffusion chronometry applied to compositionally-zoned crystals may provide the